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    <title>ShellCheck: SC2217 – Redirecting to `echo`, a command that doesn't read stdin. Bad quoting or missing `xargs`?</title>
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    <h1>SC2217 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC2217">See this page on GitHub</a>
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    <h2
id="redirecting-to-echo-a-command-that-doesnt-read-stdin-bad-quoting-or-missing-xargs">Redirecting
to <code>echo</code>, a command that doesn't read stdin. Bad quoting or
missing <code>xargs</code>?</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2217.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="op">&lt;&lt; eof</span></span>
<span id="cb1-2"><a href="SC2217.html#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="st">  Hello World</span></span>
<span id="cb1-3"><a href="SC2217.html#cb1-3" aria-hidden="true" tabindex="-1"></a><span class="op">eof</span></span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC2217.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cat</span> <span class="op">&lt;&lt; eof</span></span>
<span id="cb2-2"><a href="SC2217.html#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="st">  Hello World</span></span>
<span id="cb2-3"><a href="SC2217.html#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="op">eof</span></span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p>You are redirecting to one of several commands that don't read from
stdin.</p>
<p>This may happen when:</p>
<ul>
<li>Confusing one command for another, e.g. using <code>echo</code>
where <code>cat</code> was intended.</li>
<li>Incorrectly quoting angle brackets, e.g. using
<code>echo &lt;p&gt;Hello</code> which tries to read from a file
<code>p</code>.</li>
<li>Missing <code>xargs</code>, e.g. <code>mv -t dir &lt; files</code>
instead of <code>xargs mv -t dir &lt; files</code> (or more safely,
<code>tr '\n' '\0' &lt; files | xargs -0 mv -t dir</code>), because
stdin should be passed as parameters.</li>
</ul>
<p>Check your logic, and rewrite the command so data is passed
correctly.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>If you've overridden a command to return output, you can either
rename it to make this obvious, or <a href="ignore.html">ignore</a> this
message.</p>
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    <p style='font-size: 80%'><a href="../index.html">ShellCheck</a> is a static analysis tool for shell scripts. This page is part of its documentation.</p>
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